1. Field of Invention
This invention relates to small diameter cannula devices, systems and methods for use in conjunction with a fiberoptic scope or other instrument for use that allows a medical practitioner to visualize a particular surgical site, to introduce or remove fluids from the site, or to deliver a therapeutic treatment to the site. The cannula device has a diameter that is small enough to allow it to be used in a medical practitioner""s office for a quick diagnosis or treatment without requiring operating room time.
2. Description of Related Art
The use of fiberoptic scopes for viewing a surgical site is common practice. For example, during arthroscopic surgery, an arthroscope is introduced into a knee, shoulder, hip, or other joint. Generally, the arthroscope is attached to a camera head, a remote light source and a video monitor and inserted into a synovial joint (e.g., knee, shoulder, etc.) through a small portal incision in the overlying skin and joint capsule. Surgical instruments may be placed in the joint through similar portal incisions, with their use being guided by arthroscopic visualization. Throughout the procedure, physiologic irrigation fluid (e.g., normal saline or lactated Ringer""s) is flushed intermittently or continuously through the joint, distending the joint capsule and removing debris, thereby improving intra-articular visualization. Although irrigation liquid is typically used, it is also possible to use gas or other distension media to distend the space. As a result of widening surgical indications and the development of small diameter arthroscopes, wrist and ankle arthroscopies also have become routine.
During endoscopic surgery, endoscopes are commonly inserted into a patient through a cannula. Generally, cannulas are thin hollow tubes that, among other things, provide a tunnel between the cavity to be viewed and the outside of the patient""s body, allow rapid exchange of various endoscopes and instruments during the procedure if necessary, protect the lens at the end of the endoscope, keep soft tissue away from the endoscope, and maintain the fluid or air content of the cavity, joint or potential space. The cannula commonly stays in place for the duration of the procedure. An endoscope may be housed entirely within the cannula (for use as a traditional, rigid endoscope) or may extend from the tip of the cannula so that movement of a flexible tip is possible.
Generally, during the use of such cannulas, a trocar, which is a rigid instrument having a sharpened tip, and/or a blunt obturator, is inserted through the cannula and projects a short distance from the end of the cannula for forming a small puncture wound in the patient""s skin. This provides a route for the insertion of the cannula. The trocar is then removed, leaving the cannula in position with its distal end located in a desired position and its proximal end extending outside the patient. Various instruments may then be inserted through the cannula, such as cutting instruments, viewing instruments, irrigation tubes, and the like.
For example, some endoscope insertion cannulas have an increased diameter on the proximal end to accommodate a locking mechanism. These cannulas typically lock an endoscopy instrument in a desired position with a spring and pin-type locking mechanism. Cannulas may also have an irrigation port through which irrigation and aspiration can be introduced down the cannula tube. There are also cannulas for use in conjunction with endoscopes that are adapted to extend and retract, or to telescopically slide into various positions, based upon the desired use. Other cannulas are particularly adapted for use at locations deep within the body. Such cannulas generally have a working channel that is configured to simultaneously accept a plurality of movable instruments.
Additional introducers for various medical instruments are also available. For example, there are provided rigid tubular introducers having an internal lumen of a uniform diameter. The wall thickness of the most distal portion (the portion closest to the surgical site) varies between 0.019 inch and 0.005 inch. A Tuohy-Borst type clamp at the end of the introducer maintains the endoscope in place.
There are also endoscope sheaths which enable irrigating fluid to flush surgical debris away from the viewing end of an endoscope without contacting the endoscope itself. Such sheaths have an end cap at the end of the sheath to shield the endoscope from the surgical environment. Such sheaths also have channels to prevent communication between the endoscope and the receiving space within the sheath.
However, arthroscopic and endoscopic surgery are involved surgeries that take place under general or local anesthesia in an operating room. On the other hand, often times a practitioner may simply wish to view a particular site within the patient without actually performing surgery. For example, a surgeon may take an x-ray image of a joint and wish to see whether the tissue surrounding the joint is inflamed or irritated prior to performing surgery, or may wish to examine a surgical site post-surgery. Additionally or alternatively, a surgeon may wish to drain or irrigate a joint or deliver a therapeutic treatment to a joint, while being able to visualize the surrounding area. Optimally, in the interest of a rapid diagnosis and the least inconvenience to the patient, it is desirable for such a minimally invasive, diagnostic procedure to be performed in the practitioner""s office rather than scheduling operating room time or subjecting the patient to multiple procedures and/or appointments.
Although the medical device industry has attempted to manufacture cannula systems for in-office diagnosis, these systems have not been successful. Among other reasons, this is in part due to the poor image quality generated by the disposable scopes used and in part due to the lack of adjustability of the scope once it is placed in the sheath.
For example, there are disposable arthroscopes which generally have a 1.6 mm outer diameter and are used in conjunction with a 2.1 mm sheath. The sheath has one in-flow tube that is fixed in place on the sheath. The system is intended for office-based arthroscopy.
The connection between the sheath and the scope in this system is fixed. Once the scope is inserted into the sheath and locked into place, there is no option or mechanism that allows the scope to be moved. In other words, if the scope extends slightly from the end of the sheath, there is no way for the surgeon to maneuver the scope so that it extends further from the sheath, retracts slightly into the sheath or lies flush with the end of the sheath. The surgeon cannot compensate for slight differences in manufacturing tolerances between the scope and the sheath. Whatever view is provided in the locked position determines the surgeon""s view. Moreover, in the case of flexible fiberoptic scopes, if the scope needs to be removed and replaced, there is no locking mechanism that allows the surgeon to return the scope to its original orientation and position.
Additionally, after the procedure has been performed, the scope is disposed. It has been found, however, that lower end, disposable scopes do not offer a high resolution scope or a quality image.
Accordingly, one feature of the present invention is that it provides devices and methods that allow such diagnostic procedures to be conducted in a practitioner""s office, while providing a clear image and secure positioning, but maneuverability and adjustability, of the scope.
Another feature of the present invention is that it provides an ergonomic handle and at least one rotatable luer port for ease of use.
A further feature of this invention is that it provides a connection mechanism for attachment of a scope that allows adjustability of the scope during use.
Another feature of this invention is that it provides methods for conducting an in-office diagnostic procedure that is quick and relatively painless to the patient, while providing the surgeon with a clear view and maneuverability of the scope in use.
An additional feature of this invention is that it provides a high-quality fiberoptic scope that can be adjusted during use, and particularly, removed and then replaced in the original orientation, and that is adapted to be re-used.
Another feature of the present invention is that it provides a surgical diagnostic method that can be performed without incurring great expense and without requiring general anesthesia or actual operating room time.
The present invention provides devices, systems, and methods for obtaining a quick diagnostic view of a cavity or joint of a patient and/or delivering a therapeutic treatment to that cavity or joint. Devices according to the preferred embodiment of the invention provide high quality images because the small cannula devices are particularly adapted for use with a flexible fiberoptic scope that can be adjusted with respect to the cannula device.
A particular embodiment of the invention comprises a small diameter cannula device having a hollow tube adapted to receive an instrument, such as a fiberoptic scope, and sized for insertion into a patient for diagnosis or treatment in an office-based procedure. (As used herein, the terms xe2x80x9coffice-basedxe2x80x9d or xe2x80x9cin-officexe2x80x9d procedure means a procedure that can be performed without operating room personnel and equipment due to the minimally invasive techniques provided herein and the lack of general anesthesia or an epidural typically required for arthroscopic surgery. However, it is possible to use the current devices, systems and methods in an operating room, in a sports locker-room, on-site by paramedics, and so forth.)
The hollow tube extends from a main body which has a securing mechanism at the other end of the main body in communication with the hollow tube. The securing mechanism is adapted to receive and lock an instrument in place (in most instances, the instrument will be a fiberoptic scope, but may alternatively be a cutting instrument or other mechanical device or an energy delivery device (RF, laser, UV, and so forth). The securing mechanism also allows for at least some adjustment of the instrument such that the instrument can be adjusted to protrude from the distal end, be flush with the distal end, be retracted from the distal end into the hollow tube, and combinations thereof, while the instrument remains locked in place.
In a more specific embodiment, the main body has at least one rotatable sleeve having a connection port in communication with the hollow tube for delivering or excavating fluids or delivering therapeutic agents to a surgical site.
Further embodiments provide a rotatable sleeve with a connection port that is rotatable independent from the main body in order to prevent tubing from wrapping around the main body as the main body is manipulated. In a more particular embodiment, the connection port comprises two female luer connectors.
In an alternate embodiment, the hollow tube is surrounded by a main body that has at least one finger tang.
In a further embodiment of the invention, the device includes an adapter for changing the working length of the hollow tube allowing the cannula device to be used for both small and large joints. Specifically, the adapter may protrude from the end of the main body from which the hollow tube protrudes for shortening the insertable portion of the hollow tube and for adapting the cannula device for use in small joint procedures.
A further embodiment of the invention provides a securing mechanism for retaining an instrument in place that is adapted to allow the instrument, such as a fiberoptic scope, to be positioned within the hollow tube upon initial insertion and then repeatedly removed and reinserted without readjusting the position of the instrument or removing the cannula device to reposition the instrument. In a particular embodiment, the securing mechanism comprises an apparatus for connecting an instrument to the cannula, wherein the instrument may be at least partially inserted within the cannula, comprising (a) a linear translation mechanism for adjusting the instrument along a longitudinal axis of the cannula to a position and (b) a locking mechanism for retaining the instrument in an orientation upon initial insertion of the instrument within the cannula and adapted to allow the instrument to be removed and reinserted without readjusting the orientation or the position of the instrument or moving the cannula to reposition the instrument.
In a further embodiment, the securing mechanism comprises a main body with at least one alignment slot; an adapter body that fits at least partially within the main body and including at least one post adapted to fit in the at least one alignment slot and a j-hook slot adapted to receive a protrusion of the instrument; and a rotatable collar with at least one adjustment slot adapted to receive the at least one post, wherein the rotatable collar fits over the main body and the adapter body.
In another embodiment, the cannula device is a single-use, disposable device. In a particular embodiment, the device comprises molded plastic.
In another embodiment, the cannula device is a reusable device.
Other embodiments of the invention provide 0-ring seals at the docking port and connection port adapted to prevent fluids from passing from the cannula device to the environment.
Further embodiments include the use of the cannula system with a fiberoptic scope, a trocar, and/or a blunt obturator to assist entry of the cannula into a patient.
In use, a particular method for performing a diagnostic procedure includes providing at least one small diameter cannula device of the type described above, creating an entry path in order to deliver the cannula device to the desired surgical site, inserting the cannula device through the entry path, inserting a fiberoptic scope and securing the scope in place with the securing mechanism, and viewing the site. Specifically, the surgeon may desire to use a trocar and/or an obturator and/or make a small incision to facilitate the insertion of the cannula device. It is also possible to insert an instrument other than a scope into the cannula and/or apply an irrigation or suction tube to the connection port in order to irrigate or suction the site or to deliver a therapeutic treatment to the site. Further, an adapter may be attached to an end of the main body to shorten the insertable portion of the hollow tube and for adapting the cannula device for use with small joints.
Further embodiments of the invention provide kits for performing the methods described above.